There are lots of marking technologies including electrochemical marking, dot peen marking, and inkjet marking. However, laser engraving stands out due to its precision, accuracy, and speed. Additionally, laser engraving allows you to choose 2D or 3D engraving, depending on what you are trying to achieve. If you are looking to get your hands on a one-of-a-kind personalized gift, consider going the 3D way.
So what is 3D laser engraving and how does it work?
Simply put, 3D laser engraving is a fantastic process that creates 3D engravings of photos, designs, logos, etc. on varied materials. With 3D laser engraving, the laser is usually set to allow the dark areas of the material to receive maximum power while the lighter areas skip engraving altogether. The shades in between receive varying power for the best 3D appearance. In addition, the laser machine adds sloped edges to the product at different depths. The result is a breathtaking 3D work of art.
How 3D laser engraving works
Unlike traditional 2D marking, 3D laser engraving takes a bit of time but the results are certainly worth the effort. Essentially, your designs or photos are modeled into a 3D design via computer software.
Once your design is ready, the 3D laser machine will focus its concentrated beams of light on a specific point below the surface of the material. The process begins when each bright point in the design is plotted on the final material surface. The machine will then focus a beam on each 3D coordinate. As the beam arrives at the focal point, the high-power laser pulse makes a small inclusion or void in the material.
Once this is done, the laser will move to the next coordinate and repeats the same process to make a second etched point. It will do this repeatedly until a sufficient number of points have been created to reproduce the intended design within the material. The laser machine typically emits a high-power output for darker areas and automatically decreases the power when the image becomes lighter.
The higher the power output from the machine, the deeper the laser burn and the lower the power output, the shallower the burn and hence the less material will be burned. Depending on the material in question, you might need to clean the surface of the product after engraving to get rid of debris. This is especially true for wood as it tends to give off a lot of oil residue during the intense heat exposure.
What is the difference between 2D and 3D laser engraving?
In 2D laser engraving, a photo or design is defined by its width and length with the depth being constant across the working area. In other words, each engraved cut or pixel is created at the same depth over the entire piece. With 3D laser engraving, the engravings are defined by width, length, and varying heights. The engraved art is therefore characterized by valleys and hills. The process of 3D laser engraving can be defined as the art of burning away some parts of a material to give varying depths to the background.
Why is 3D laser engraving necessary?
3D laser engraving comes with a host of benefits not only for individuals running a home-based laser engraving business but for big companies too. Here are some of the important advantages;
- Flexibility: 3D laser systems have the ability to produce clear engravings on non-flat surfaces. These include round shapes, cylindrical shapes, conical shapes, parts with concave/convex portions, triangular shapes, and sloped surfaces. Additionally, a 3D laser machine can engrave objects at different heights. This is because it can easily adjust the laser beam position and the laser focal length, a task that is impossible with a 2D laser.
- Better marking effect: A 3D laser engraver has a larger working area (can have a lens of 500*500, 600*600, etc.) compared to a 2D engraver (300*300 lens). It also employs a front focusing optical mode that makes use of a larger X, Y-axis that offers a good deflection of the lens. These are beneficial in increasing the integrity of the marking effect and better focus accuracy.
- Ideal for deep engraving: With 2D engraving, deep surface carving is quite tricky. As the focus of the laser ascends during the process of engraving, there will be a sharp drop on the laser energy of the actual surface of the object. This has a direct effect on the efficiency of the engraving. On the flip side, 3D engraving is devoid of this challenge and is, therefore, more suitable for deep engraving.
- Allows for multi-color engraving: when aiming for multi-color engravings, using 2D machines is possible but it can be quite limiting. 3D machines, on the other hand, can perform plane processing of multi-color effects.
- Better personalization: there’s no denying the fact that 3D engraved laser items are highly personalized. The technology provides exacting accuracy that brings an otherwise 2D image to life in a unique and beautiful way. With 3D laser engraving, you can let your mind run wild as you bring otherwise bland designs and photos of varying sizes to life thereby creating a perfect 3D gift.
- Quality marking: 3D engraving offers high-quality marks with clean mark edges. Laser beams are non-invasive meaning your products will have no marks or blemishes.
Suitable materials for 3D laser engraving
3D laser engraving doesn’t work for all materials that might support 2D laser engraving. Stone, for instance, is not a good candidate for any 3D engraving project. This is because it is too hard and poses a challenge of burning the material without having the beam travel all the way through the material. The following are the best materials for 3D laser engraving:
- Hardwood: This is undoubtedly the most ideal material for 3D engraving in the industry. Hardwood species such as birch, cherry, walnut, and maple are characterized by a fantastic grain structure that best highlights the engraving details. Sure, the wood will be burnt during the laser engraving but the soot is quite easy to clean up using water.
- Acrylic: acrylic comes at a close second to wood when doing three-dimensional laser engraving. Although harder than wood, acrylic has an impressive melting point that is capable of producing great 3D designs and images. However, if you are using clear acrylic, you may have to make a second pass with the machine to perfectly gloss or polish the surface of the engraving.
- Medium Density Fiberboard (MDF): if you are looking for an engraved product that you can paint later, consider using MDF. It is soft, readily available, and quite affordable. Once you are done engraving, you can clean the surface using an air hose and a damp cloth and then proceed to paint it.
Tips and tricks to make 3D laser engraving easier
- Buy the right machine
Perhaps the most important thing to keep in mind before any 3D laser engraving project is the choice of the machine to be used. Apart from getting a laser that can interpret a wide range of color shades, you need one capable of quick pulse durations. There’s an unwritten rule that lasers with radio frequency (RF) ceramic or metal tubes do a better job than those with direct current (DC) tubes when it comes to 3D engraving. Scientifically, RF lasers offer quicker pulse rates that are perfect for 3D projects whereas DC lasers are characterized by a lower modulation speed that fails to fire quickly like RF lasers.
The machine should also be powerful enough to be able to handle massive engraving projects in no time. The recommended wattage for 3D laser engraving is 100-400 watts. In all honesty, lower wattage machines will still get the job done but higher wattage lasers will give you total relief depth plus a much larger variation between the maximum and minimum depth areas.
- Get the appropriate depth of the engraving
You also need to give thought to the depth of your 3D engravings. If you are using wood, it is easy to make deep cuts because the machine can cut through a one-inch wood piece with relative ease. However, you might want to keep your engravings shallow to clearly display your engravings. It is a good advanceable to keep your engraving depth in the range of 1/8” and ¼”.
- The artwork should be perfectly designed
The most challenging part of the 3D laser engraving is creating the pattern and design. If you are a beginner, it can be time-consuming and brain-racking. Thankfully, you will get the feel of things before you know it. Design software typically use a palette or grayscale to create high resolution 3D graphic designs and images. Your designs should be clear in order to create equally eye-catching 3D logos, picture frames, cutting boards, and other products. This means that you have to properly understand the specific software you are working with. You should be able to shade your artwork in gray so that you determine the depth of your image. The best graphic design software is one that 8-bit or one that correlates to all the 256 shades of gray between white and black. Some of the popular software that meet these criteria are Photoshop, CorelDraw, Adobe Illustrator, Cimigrafu and ArtCAM.
From getting the artwork right to varying the depth of the engraving, you need a generous amount of patience to nail 3D laser engraving. The time taken depends on the laser power, the resolution of your artwork and its size. Once you get the hang of things, you’ll know the right balance for these parameters to get quality 3D engraving using the least amount of time possible. But patience is an important virtue when it comes to 3D laser engraving.